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WorksheetsETC 603- ELECTRICAL FAULTS
Total questions: 55
Worksheet time: 9hrs 10mins
Electrical fault occurs when electric current flow is _______ the current rating of the conductor, equipment and other devices.
more than
equal to
less than
Short circuit happens when the insulation damage allows the flow of current between _________.
conductors
insulator
_______ happen due to the damage of the conductor's insulation.
Ground fault
overload
What type of fault is described in A?
line to line
line to ground
What type of fault is described in B?
double line to ground fault
single line to ground fault
line to line fault
What type of fault is described in C?
single line to ground fault
line to line fault
double line to ground fault
This device will protect against _________.
overload only
short circuit only
both short circuit and overload
This device will protect against _________.
overload only
short circuit only
both short circuit and overload
Lightning can cause ________.
overload
voltage surges
When there is overload, the circuit breaker must be ______ to protect the circuit.
OPEN
CLOSE
A material that carries electrical current.
conductor
insulator
A material that does not carry an electrical current.
conductor
insulator
Good conductor has very _______ resistance.
low
high
The size of the conductor is relative to its ______ rating.
current rating
voltage rating
Which is not a factor of conductor current rating?
weight
material
size
temperature
There are two conductors that are mostly found in the market, the copper and __________.
aluminum
gold
The breakers and relays that can quickly isolate the fault is called ________.
instantaneous
inverse time delay
The protection system should be _________, so only equipment directly affected by the fault will trip.
coordinated
tuned
___________ fuses must be used in motor circuits so that the increase of motor starting does not blow the fuse.
instantaneous
time delay
To limit the amount of current to the ground, a _______ will be connected in series.
resistor
capacitor
Ground fault circuit interrupter (GFCI) is used for ground fault protection in _______ voltage circuits.
low
medium
high
The GFCI monitor the current between the line and the ground and will sense any ___________.
imbalance
overcurrent
A low resistance ground fault provides a path for _____ current to flow.
very high
very low
Voltage surges can happen from switching or _________.
lightning
sunlight
Which of the following is not a type of conductor?
glass
aluminum
copper
steel
Which of the following is not a type of insulator?
glass
aluminum
plastic
wood
1 mil = ______ inch
0.001
0.1
When there is a short circuit, there is a possibility of arc flash.
TRUE
FALSE
_________ happens when the insulation damage allows the flow of current between conductors.
short circuit
overcurrent
The ______ of the conductor is relative to its current rating.
size
color
Identify the protection device shown in the picture.
overload relay
circuit breaker
Identify the protection device shown in the picture.
overload relay
circuit breaker
Identify the protection device shown in the picture.
overload relay
circuit breaker
Identify the protection device shown in the picture.
overload relay
fuse
___________ is a phenomenon where a flashover of electric current produced hot air as a result of electric fault.
arc flash
electric shock
The temperature of an arc flas can go as high as _______ degrees Fareinheit.
35,000
75,000
The earth-fault relay is therefore completely unaffected by load currents.
TRUE
FALSE
GFCI will activate when the current going to the load is ________ the current returning to the source.
less than
more than
equal to
Which of the following is not a cause of overcurrent?
overload
short circuit
ground fault
over-frequency
The rated voltage of the breaker is the ______ voltage at which the breaker should be used
highest
lowest
When heated with excessive current, the fusibe link of the fuse will be ____________.
destroyed
deformed
The GFCI has overcurrent protection.
TRUE
FALSE
The overload relay has ground fault protection.
TRUE
FALSE
The circuit breaker has both overcurrent and short circuit protection.
TRUE
FALSE
Which of the following type of fuses is rated up to 60 Amperes at 125 Volts, 250 Volts and 600 Volts.
knife blade
non-contact
ferrule
contact
Which of the following fuses can be used in situations where
plug
dual element
contact
time lag
The picture below indicates _________.
damaged fuse
operational fuse
Which of the following will not cause a fuse to blow.
undercurrent condition
overcurrent condition
starting a motor under haeavy load
Which of the following are used to interlock various pieces of equipment and ensure proper starting and starting sequence?
auxilliary contacts
main contacts
arc quench
Air Circuit breakers are usually used in _________.
600 Volts and below
34.5 kV
69 kV
Identify the part of the fuse labeled with the letter A.
fusible element
casing
Identify the part of the fuse labeled with the letter B
fusible element
casing
What do you call this fuse?
ferrule
Time lag
What do you call this fuse?
dual element
Time lag
Identify the part of fuse described in A?
spring
end caps
